1. Field of the Invention
This invention relates generally to propeller fans, and more particularly to a one-piece blank for a propeller fan.
2. Description of the Prior Art
Propeller fans for air moving applications are commonly formed from a one-piece blank of relatively thin sheet metal, the blank and formed fan having a plurality of blade portions which extend outwardly from a central hub portion by which the fan blade is mounted on a driving member. A wide variety of blade configurations has been proposed for improving the efficiency of air delivery and/or reducing blade noise, it being well known that the noise generated by a propeller fan is affected by the number of blades, the contour and form of the individual blades, the outside diameter of the fan and the velocity of rotation.